Every domain name is assigned to two or more DNS servers (often called name servers). These DNS servers holds the information regarding the ip addresses associated with the domain name.
The process of assigning dns servers to your domain name is called "redelegation". This is often done when you want to change your web host. By redelegating your domain name to Quadra Hosting's dns server, you are "moving" or "pointing" your domain name to your new account with Quadra Hosting.
When you have just added your domain name on your Quadra Hosting control panel, the system will create the necessary entries in the DNS servers. You need to make note of which DNS servers you have been assigned to for the domain you've just added. This can be found in the control panel -> Domains.
Next, you need to redelegate your domain name so that it will point to your Quadra Hosting account space. To do this, you need to login to your domain name registrar - the company that registered your domain name. They would normally have an area for you to make changes to modify the dns servers (name servers) your domain is assigned to.
Once this is done, it would take between 12 - 72 hours before your domain will actually point to our server, due to DNS caching.